Persons receiving calls at call centers or other places of business often have to place callers on hold while they search for requested information or respond to other callers. Meanwhile, the party on hold is bound to an unproductive telephone call and may grow impatient as hold times lengthen. Operators of telecommunication networks have responded to this problem in various ways, such as by providing voice messaging systems to which on-hold parties can leave voice messages, and implementing more intelligent hold queues that inform callers of projected remaining hold times. Problems associated with hold times remain despite these responses. In particular, a voice messaging system is essentially a delayed hold queue that requires agents to parse through perhaps hundreds of saved messages. Also, projections of hold times can be inaccurate or otherwise do little to free callers from unproductive telephone calls.
Telecommunication network operators have also responded to the problem of long call hold times by implementing a calling feature generally described herein as “hold-call-back.” A hold-call-back feature allows a caller, in response to a call being placed on hold, to disconnect the call and request a call-back at a later time. Upon attempting to take the initial call off hold and discovering that the call has been disconnected, the called party can supply a command for initiating the call-back to the original caller. Existing implementations of hold-call-back calling features are burdensome and expensive; they rely on the switching devices of the Public Switching Telephony Network (PSTN) and require customization of the logic and signaling performed by those devices. In some cases they require the use of additional devices, such as Private Branch Exchanges (PBX) and/or other peripheral or adjunct systems. Therefore, what is needed is a more efficient implementation of a call-hold-back calling feature that does not rely on PSTN devices.